Seaming machine



Feb. 5, 1946. my 2,394,413

SEAMING MACHINE Filed Dec. 12, 1941 2 Sheets-Sheet l INVENTOR.

' Z60 Per/y, %2

L. PERRY.

SEAMING- MACHINE Feb. 5, 1946.

Filed Dec. 12, 1941 1 2 Sheets-Sheet 2 INVENTOR.

Patented Feb. 5, 1946 UNITED STATES PATENT OFFICE 2,394,473 7 SEAMINGMACHINE Leo Perry, Whitewater, Wis. 7 7 Application December 12, 1941,[Serial No. 422,781

1 Claim.

My invention relates to a machine for joining sections of syntheticfabrics, particularly fabrics that unite by the application of heat andpressure. 4

Difiiculty has been experienced in forming garments composed partly orwholly of flexible or pliable sheets of synthetic material, due to thedifiiculties in controlling the heat, the degree of pressure and thetime of treatment, since there is a critical period of time andtemperature which may not be varied. Different materials have differentcritical periods but each may be treated satisfactorily withoutvariation in the two elements of pressure and time. This leaves as theonly necessary variation a capacity for variation in the degree of heatapplied.

I have found that by the use of fixed and movable seam-engagingelements, the movable element carrying a heating device having means formaintaining a definite controlled temperature, together with means foreffecting cyclic movement, I am able to form the described seams withcomplete certainty. The matter of certainty involves the completion ofthe seam from end to end without interruptions and without suchoverheating as would weaken or cause deterioration of the material atthe seam.

Machines such as herein disclosed are used extensively for producingwaterproof garments for use by government forces as well as for civilianuse.

A machine such as contemplated is illustrated in the accompanyingdrawings; in which:

Fig. 1 is a side elevation;

Fi 2 is an end elevation;

Fig. 3 is an enlarged sectional view on the line 3-3 of Fig. 1; and,

Fig. 4 is an enlarged detailed View showing the means for shutting offthe motor at the completion of a cycle.

The machine comprises a frame including legs I0, 2, bed or bar ll havinga padded upper surface [2 and a cross bar l3. On the cross-bar ismounted a constant speed motor l4 connected by a belt and pulley to areducing gear box IS. A chain l6 connects the pinion on the gear box toa sprocket wheel I! mounted on a transverse shaft I8. The shaft alsocarries a cam l9 which actuates an arm 20 fixed to a shaft 2|, the endsof which project outside of the frame and carry arms 22 at each end. Atension spring 23 tends to hold the arm 20 against the cam. A sprocketwheel 24 also mounted on the shaft l8 connects the shaft through a chain25 to a sprocket wheel 26 fixed to a shaft 21, this shaft carrying anarm 28 having a roller 29 thereon which lies against the arm 20 andsupplements the action of the spring 23 in positively holding the armagainst the cam.

The arms 22 are connected to the bar 33 containing the heating element,the bar comprising, as best shown in Fig. 3, a channel iron 34., in thecavity of which is a heating element .32, indicated generally, and athermostatic tube 33. Thevspace above the heating element is filled withan ins-ulating material 34 and a channel shaped cap 35 encloses thechannel. A narrow plate 36 is secured to the bottom face of the channeland acts as the heat transmission element or iron. In order that Fig. 3may not be confusing, I have omitted the arm 22 and its connection tothe heating bar. The bars Il30 are of considerable length, adapting themachine for use in making seams of substantial length or of any shorterlength, each garment including a number of seams of varying length.

Current is supplied to the motor through a switch 31 having a switch arm38 and mounted on the frame member II. An arm 39 carried by the heatingbar 30 carries a pivoted finger 40, as best shown in Figs. 1 and 4, thefinger being so positioned that as the arm moves downwardly toward aposition in which the heating element is moving toward contactposition,the finger will ride .over the switch arm 38 without moving the latter.However, toward the completion of the cycle and when the heating elementis moving away from the contact position, the finger 40 will contact theswitch arm in the dotted line position of Fig. 4, which is the onposition and move the switch arm to the full line position of Fig. 4which is the off position.

In operation the heating element having been energized and raised to adefinite temperature as controlled by the regulating knob 4i carried bythe arm 42 on the heating bar, the operator manually moves the switcharm 38 to the dotted line position. The motor will start its operation,rotating the cam I9 to oscillate the arms 2022 and lower the heating barinto pressure relation with the contact pad, it being assumed that thesections of synthetic material have been placed in proper position onthe pad. The length of time during which the pressure and heat areapplied is determined by the dwell of the cam, the speed of the motorand the gear reduction. Thus the operator cannot vary the time elementor cause misoperation by attempting to substitute his judgment as to thetime of contact. Of course, the dwell may be varied by substituting acam any variation inthe requirements for properseaL 'ing may be made byvarying the temperature ofthe heating element through the control knob).

' Asthe cam approaches a completion Of one revolution the heating barwill be approaching its elevated position at which point the arm 39 andfinger dilwill actuate the switch arm 38toi interrupt the motor, thisserving to complete a 7 yc h 'e y l m e itiated-by the 10 elementassociated therewith means for conc c trolling the temperature-of saidheatingelement" ope'ratorand is completed 'by the machine itself; Thisenables the operator to take the necessary time for the preparation ofthe two sections offj.

material and placing of them in proper vposition 'for the seamingoperation.

It is possible that the heating element vmight; be placed in the fixedbar, the movable bar having a resilient face for pressing materialsagainst; the heating bar. This is not recommended, however, ,since the'act' of placing the two sections of material in po'sition to be'joinedrequires a defi nitelengtli of time "and 'mustbedone' manually. Thusdifficulty would be experienced in holding the material with the fingerson the hotsurface While waiting for the machine to function,

- Other means than'those shown may be pro- V vided iforstopping andstarting the operation and l the "shape and extent of the heating barand cooperating pad may be varied to suit difierent garments "or otherarticles being manufactured, Q

and I do not'wish to be'limited except as indicated in the appendedclaim. I claim; a 7 V V A machine forheat sealing flexible synthetic 5thin sheet material comprising an elongated unheated seam-forming bar,means for mounting said bar' in substantially fixed position, ashiftable elongated seam-formingibar cooperable with the fixed bar; saidshiftable bar havinga heating so as to maintain the shiftablebar at atemperatlfre to heat seal synthetic sheet material, said shiftable barnormally being mounted in' spaced "1'5 relationfrom the fixed bar," andpower operated I iicyclically operable shiftingmeans for shifting the c.Tshiftable bar intoengagement with the fixed bar,

' said shifting means including an electric motor,

a control: switch for energizingrthe motor, and V 20 m nst ri en by hemotor for ov ng s id t o. q e nd rhfl im a in con ct 7 for a periodin'respect'tq the contacting pressure and temperature of theheated barsufilcienflto r Y heat sealisynthetic sheet material superposed- 25 nnfl bar; a d t r a te t efielct automatic separation oi said bars,deenergigethe control switch, and hold the bars in separated relationb

